Telpher line with contactless energy and data transmission

ABSTRACT

In an electric telpher system with non-contact power transmission between a feeder ( 4 ) placed at a spacing along a slide rail ( 1 ) for mobile transfer units ( 12 ) and an inductive current collector on the transfer unit, a data transmission loop ( 7 ) is arranged at a defined distance from the feeder for non-contact data transmission between a central control station ( 18 ) and the transfer units in such a way that its parallel conductors are located exactly within a field line of the feeder. The data transmission loop is direct-coupled with the central control station via a transmission station ( 10 ). Each transfer unit is equipped with a communication module ( 6 ) with transmit and receive coils on ferrite cores for inductive data transmission to ensure that these units can receive all information exchanged via the data transmission loop. The data transmitted by means of induction consists in sinusoidal signal sequences at two different fixed frequencies in the medium frequency range that serve as digital signals.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an electric telpher with non-contact powertransmission between a feeder arranged at a spacing along a slide railfor mobile transfer units and an inductive current collector on thetransfer unit as well as with non-contact data transmission between acentral control station and a controller installed on the transfer unit.

2. Background Art

In a known electric telpher system of this type, the return conductorfor the feeder that is connected to a higher-frequency AC power sourceis the slide rail for the mobile transfer units that are equipped with adrive unit and a controller. The current collector is a ferrite corethat encompasses the feeder in a U-shape with windings attached to itslimbs designed for producing different feed voltages for the drive unitand the controller of the mobile transfer unit, respectively.

The initial proposal made here to also use the feeder for communicationto program and remote-control the transfer units from a central controlstation is not feasible in practice because there is a very smallsignal-to-noise ratio due to the high current in the feeder and theaccordingly high field density and because eliminating the resultingproblems would require an unjustifiably great electrical and electroniceffort.

Infrared technology is another option for non-contact data transmissionin electric telpher systems. However, a data transmission systemdesigned on this basis has spatial constraints. Data can only betransmitted from specific, locally separated points. In the meantime thetransfer units are uncontrolled and cannot be influenced from outside.Reducing the distance between these communication points requires greatexpenditure, however.

It has also been proposed to use radio technology for data transmission;each transfer unit is equipped with a radio module and a group ofoverlapping radio cells is set up along the track between which thetransfer units are handed over. The disadvantage of this technology isthat radio contact can be impaired or lost due to external factors.Also, transfer from one radio station to another requires a majorinformation technology effort.

It is the problem of this invention to develop a non-contact datacommunication system for an electric telpher with non-contact powertransmission of the type mentioned above that ensures permanent centralcollection of information from the mobile transfer units and datatransfer to control the operation of the mobile transfer units in acost-efficient way and also guarantees that the information sent to thecentral control station is simultaneously received by all mobiletransfer units.

SUMMARY OF THE INVENTION

The inventive idea is based on inductive power transmission from afeeder conducted along the slide way to the power consumers of thetransfer unit and characterized in that a data-transmission loop whoseconductors are direct-coupled with a central control station andinductively connected to the controllers of the transfer units isattached at a spacing to the feeder. The non-contact connection with theinductive data transmission loop is established via a communicationmodule attached to the mobile transfer unit, said module comprisingtransmit and receive ferrite cores with a transmit or receive coil andbeing arranged at a small but practicable distance for the motion of thetransfer units in parallel to the data transmission loop. Data istransmitted in the medium frequency range at two different, fixedsinusoidal frequencies, each representing a digital value (0 or 1).

The geometrical arrangement of the data transmission loop in front ofthe feeder in a single field line generated by the feeder ensures thatany noise voltage induced by the feeder and its interference withinductive data transmission is low. Using inductive data transmission inthe medium frequency range in the form of two different sinusoidalfrequencies as digital data sequences, the data transmission loopaccording to the invention is a pure inductive loop not used as awaveguide or as an antenna with high-frequency electromagneticradiation, which ensures low circuit complexity, uncritical andpracticable dimensioning of terminating resistors for the datatransmission loop and, last but not least, a sufficient signal-to-noiseratio between the power and the data transmission channels. The spacingsbetween the data transmission loop and the transmit and receive ferritecores attached to the mobile transfer unit are 5 to 10 mm and thussufficiently wide for operating an electric telpher.

In an improved embodiment of this invention, the transmit and receiveferrite cores in the communication module are assigned to a transmit andreceive coupler, a transmit and receive section, and a processing unitfor transmitting or receiving and for generation and processing of dataor digital sinusoidal sequences at two different frequencies. Suchtransmit and receive couplers as well as transmit and receive sectionswith processing unit are also provided at a transmission stationinserted between the data transmission loop and the central controlstation.

In the present electric telpher system with non-contact power and datatransmission, the communication path matches exactly the path of themobile transport units. The data transmission system operated at lowfrequencies is capable of providing all mobile transfer units with dataat low cost and at all times and control them accordingly, or ofcollecting information provided by these about transfer unit status,position, or distances between units and forwarding it to the centralcontrol station.

The transfer units designed according to the invention cansimultaneously receive all information sent to the transmission station.In this way, a direction-independent anticollision function of themobile transfer units can be implemented along the transport route byspecific control sequences in the respective controller, without anyneed for additional peripherals. This local operational anticollisionprotection of the mobile transport units described above can be adjustedto systematic distance requirements, which is a decisive advantage ascompared to all known methods along a physical transport route.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention is explained in greater detail below withreference to the figures. Wherein:

FIG. 1 is a schematic representation of an electric telpher system withnon-contact data communication between its mobile transfer units and acentral control station via an inductive data transmission loop;

FIG. 2 shows an inductive communication module integrated in a mobiletransfer unit for transmitting data between a central control stationand a transfer unit via the data transmission loop;

FIG. 3 shows the data transmission loop and a transmission stationconnected to it;

FIG. 4 shows a block diagram of a mobile transfer unit, and

FIG. 5 shows a perspective view of a feeder bracket connected to theslide rail for the transfer units with a slip-on holder for the datatransmission loop.

DETAILED DESCRIPTION OF THE DRAWINGS

FIGS. 1 through 5 relate to an electric telpher system with non-contactinductive power transmission from a feeder to a multitude of mobiletransfer units 12 that can travel on a slide rail 1 for carrying andhauling loads. Each mobile transfer unit 12 is equipped with a currentcollector 14 for non-contact power transmission from the feeder 4 thatis connected to a power source and designed as a stranded conductor. Thefeeder 4 is arranged in the holding duct 3 of a feeder bracket 2 that isattached to the slide rail 1 and made of non-conductive material. As canbe seen from FIG. 5, the feeder 2 comprises a mechanical coding 2 a toallow for absolute position detection of the transfer unit 12 using aposition scanner 17 (FIG. 4) attached to the transfer unit 12. Thecurrent collector 14 for inductive non-contact power transmission isdesigned as a U-shaped ferrite core with two windings and one electroniccollector circuit per winding (not shown) to supply a controller 13mounted to the transfer unit 12 as well as any associated sensing andcontrol equipment 16 and the position scanner 17 with the requiredcontrol voltage and to supply the drive unit 15 of the transfer unit 12with the required higher drive power.

The ferrite core (not shown) encompasses the feeder 4 in such a way thatthe magnetic field lines 4.1 of the feeder 4 ensure the formation of amagnetic flux in the ferrite core for a sufficient magnetomotive force.

The transfer units 12 that are guided on the slide rail 1 and a centralcontrol station 18 exchange non-contact data signals by means ofinduction in the electric telpher with inductive power transmission asdescribed above. A data transmission loop 7 consisting of two parallelwires 7 a, 7 b that are vertically stacked in the drawing plane isplaced at a spacing and in parallel in front of the feeder 4. The twowires (conductors) 7 a, 7 b are connected at their respective ends by aterminating resistor R₂. The data transmission loop 7 is located in ageometrical position along (i.e., within), a field line 4.1 of thefeeder 4 so that any interfering effects from the magnetic field on thedata transmission loop 7 are minor. The exact geometrical arrangement ofthe data transmission loop 7 along a field line of the feeder 4 isachieved by means of a holder 5 to which the wires 7 a, 7 b are fixed inparallel and which comprises two holding ducts 5 a, 5 b. The holder 5 isdesigned as a slip-on element that can be locked onto the mountinggroove 3 for the feeder 4.

According to FIG. 1, the electric telpher system in the presentembodiment includes two sections (1 and 2) and therefore also two datatransmission loops 7 with their associated terminating resistors R₂.Each data transmission loop 7 is direct-coupled via data feed lines 11with a transmission station 10, and each transmission station 10 itselfis connected to a central control station 18. The transmission station10 includes a transmit and receive coupler 10.1 as well as a transmitsection 10.2 and a receive section 10.3 for transmitting or receivingsinusoidal signals in the medium frequency range at two different fixedfrequencies with a sufficient signal-to-noise ratio, in the present casebetween 50 kHz and 125 kHz. The sinusoidal signals that occur as twofixed frequencies in serial sequence represent coded digital 0/1signals. A processing unit 10.4 connected to the transmit and to thereceive sections 10.2, 10.3 is linked with the central control station18 via the respective transmission station 10.

An inductive communication module 6 that is provided on each transferunit 12 also includes a transmit and a receive coupler 6.3 and 6.4, atransmit section 6.5 and a receive section 6.6, for transmitting orreceiving two sinusoidal signals or signal sequences at different fixedfrequencies in the medium frequency range as digital data signals, and aprocessing unit 6.7 that is connected to a controller 13.

Data transmission, i.e. transmitting and receiving data back and forthat two fixed frequencies in the form of sinusoidal signal sequences viathe data transmission loop that is direct-coupled with the transmissionstations or from the communication module 6 on the transfer units 12 isinductive and non-contact. For this purpose, the communication module 6is equipped with two E-shaped ferrite cores, the transmit ferrite core6.1 comprising a transmit coil 8 and the receive ferrite core 6.2located behind it in the drawing plane (not shown) comprising a receivecoil 9, to send sinusoidal signals at different frequencies thatcorrespond to digital pulse sequences (0; 1) from the controller 13 viathe communication module 6 and the data transmission loop 7 to thetransmission station 10 and to the central control station 18, orreceive data in reverse direction and forward it via the processing unit6.7 to the controller 13 to control, for example, the drive unit 15.

The invention is not limited to the embodiment described above, ofcourse. Within the scope of characteristics relevant to the inventionwhich, for an electric telpher with non-contact (inductive) powertransmission to the transfer units, consist in likewise inductive datacommunication between the transfer units and a central control stationby means of two sinusoidal wave sequences of different frequencies via adata transmission loop with terminating resistors at both ends andparallel wires located within a magnetic field line of the feeder forinductive power transmission using ferrite cores, each equipped with atransmit or receive coil, expert modifications are conceivable forimplementing higher-order functionality such as visualization,preventive maintenance, or centralized anticollision protection.

1. An electric telpher with non-contact power transmission between a feeder arranged at a spacing along a slide rail for a mobile transfer unit and an inductive current collector on the transfer unit as well as with non-contact data transmission between a central control station and a controller installed in the transfer unit, wherein a data transmission loop with terminating resistors at both ends and two parallel conductors that are located in one and the same field line of the feeder is arranged at a defined spacing along the feeder, in that said data transmission loop is direct-coupled with a central control station via a transmission station and inductively connected with the controller of the transfer unit via a communication module; said communication module comprising transmit and receive ferrite cores with a transmit or receive coil at a spacing to the data transmission loop for inductive transmission of digital signals in the form of sinusoidal sequences at two different frequencies in a medium frequency range.
 2. The electric telpher according to claim 1, wherein a holder can be mounted to a feeder bracket that holds the feeder, wherein the two conductors of the data transmission loop can be fixed in parallel to each other in holding ducts.
 3. The electric telpher according to claim 2, wherein the holder is designed as a slide-on accessory bridging a holding duct of the feeder bracket.
 4. The electric telpher according to claim 1, wherein the transmit and receive ferrite cores have an E-shaped design and in that respective center webs that face the data transmission loop at a distance house either a transmit coil or a receive coil.
 5. The electric telpher according to claim 4, wherein a transmit and a receive coupler, a transmit and a receive section, and a processing unit connected to the controller are assigned to the transmit and receive ferrite cores in the communication module.
 6. The electric telpher according to claim 1, wherein the transmission station connected to the data transmission loop via a data feed line comprises a transmit and receive coupler, a transmit and a receive section as well as a processing unit connected to the central control station.
 7. The electric telpher according to claim 1, wherein the two different fixed frequencies of coded digital data transmitted by induction are sinusoidal signals with a sufficient signal-to-noise ratio.
 8. The electric telpher according to claim 1, wherein the controller of the mobile transfer unit is connected to a drive unit, sensing and control equipment, and a position scanner.
 9. The electric telpher according to claim 1, wherein each of multiple telpher sections is assigned to a data transmission loop and a transmission station connected to it.
 10. The electric telpher according to claim 1, wherein the capability of the transfer units to receive all data transmitted on the data transmission loop can be used for a local, direction-independent collision protection function of all mobile transfer units. 